Thermostatic control device for water heaters



Feb. 28, 1928.

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J, G. wRAGG THERMOSTATIC CONTROL DEVICE FOR WATER HEATERS Filed Nov. 8.1926 2 Sheets-Sheet 2 ...if k

vwent-oz: 1mm

`Patented Feb. 28, 1928.

UNITED. 'STATI-:s

JOHN G. WAGG, OIE NEW LONDON, CONNECTIOUT.

THERMOSTATIC CONTROL DEVICE FOR WATER HEATERS.

Application filed November 8,1926. Serial No. 146,996.

The invention vrela-tes to water `heating systems, and particularly tothat class of such apparatus in which the heating means for the waterare automatically controlled and caused to function by the falling ofthe temperature of the water in the neighborhood of such heating meansor by the flow of cold water thereto, and in which the func-` of thiskind previously known in the art.'

Other objects of the invention will appear from the followingspecification.

' The invention consists in the novel construction.A arrangement andcombination of various devices. elements and parts, as set forth in theclaims hereof, one'embodiment ofthe same being illustrated in the accon1- panying 'drawings and described in this specification.

In the accompanying drawings,

Fig. 1 is a vertical sectional view of an embodiment of my invention;

Fig. 2 is a detail view showing an indicator device which may be used inconnection with theinvention or as a part of the same; and

Figs. 3 and 4 are vertical sectional views showing on an enlarged scalea detail of the invention, as hereinafter more fully described.

My invention is intended to be carried into effect infconnection with ahot water tank, or, as it is usually called, b'oiler, which may be ofany size, shape or construction suitable for the purpose. As waterreceptacles of this' description are well understood in the art, I haveshown the same in the 'drawings only in a fragmentary Way, the referencenumeral 11 in Fig. 1 being intended'to designate a portion ofthe wall ofsuch a water receptacle, the same being provided with an aperture in thepart shown in Fig. 1, which is internally screw-threaded so as to beadapted to receive the screw-threaded nipple 12 which projects from thevalve chamber forming a part of my invention, as shown in thisparticular embodiment thereof. The

boiler" is supported in any suitable manner, and is provided with aninlet pipe for filling the same with water and an outlet pipe, as willbe well understood.

The means for heating the water in the boiler form no part of myinvention, and I have therefore neither shown nor described the same. Mypresent invention relates more particularly to the control of suchwaterheating means, and in the here described and illustrated embodimentof the invention, I have shown a method of controlling the flow of gasto such heating means.

Referring moreparticularly to Fig. 1, 13

-shows' the gas inlet pipe, and 14 indicates the beginning of a by-pas'sto al pilot light ,of the usual or any suitable construction.

This gas inlet pipe is shown of van elbow form, andopens into the mainvalve chamber to the right, hereinafter specifically described. Thisvalve chamber is closed at the top by a screw-threaded cap 15, and hasan opening 16 in the bottom, leading to Athe burner. The valve chamberis designated 17 In the upper part ofthe valve chamber is positioned adisk member 18 havin a gas passage 22. The upper surface of this' member18 is of sloping form as shown in the drawings and' is provided with anupward extending annular iange 19. Over the mem-- ber 18 is positionedthe valve 20, which is provided with a central recess 21 adapted toengage with the annular flange 19. Posi- I tioned in the valve 20 andextending downwards into the recess 21 is 'a plug 23, which lis adaptedto engage with'the valve-operating devices now to be described, so thatthe valve may be raised or lowered as the thermostatic control isaffected by the temperature of the water in the boiler.

In the lower part of the valve chamber, and bridging though not closing,the gas outlet 16, is a supporting bar 24. -Upon this bar isisupportedthe lower end of a lever 25, which is provided with a notch-at its upperend adapted to receive one end of a U-spring 26, the other end of whichis seated in a similar notch in the lower end `of a short lever 27pivotally secured to the member 18 as shown at 28. The member 27 extendsupwardly through on opening 1n the member 18, so as to come into contactwlth the member 23 in the valve. A

In the sidewall of the valve chamber, near the bottom, is insertedascrew plug 30,' having a pointed end 31 which enters a suitable socketin the lower part of the lever 25.

The plug 30 is provided with a disk 32 for rotating the same and therebyadjusting the lateral position of the point 31, and this disk' may ifdesired be graduated so as to be read in connection with a pointer 33,for convenengage with a suitable socket in the member 25, and the otherend of which is contained in a sleeve 36 which extends laterally intothe boiler, the inner end being closed by a screw plu 37. The sleeve 36should be of a materia having a substantially different coeiiicient ofexpansion under thel action@ of heat from that of the rod 34.

Extending into the upper part of the valve chamber .are ladjustingscrews 40` and 41, which are adapted to prevent undue lateral swing ofthe member 25. A spiral spring 42 is interposed between thev upper partof the lever 25 and the wall of the valve chamber, adapted by extensionto swing the member 25 to the right when the sleeve 36 expandssuiiiciently to permitsuch swing.

The operation of my invention is-as fol.

lows.: Gas is admitted through the inlet 13, passes into the valvechamber, if the valve be open to admit same, and through the outlet 16to the main burner (not shown). portion of the gas is carried lby theby-pass 14 to the pilot light (not shown) adjacent j. the main burner.Assuming the parts to be in th-e position shown in Flgs. 1 and 3, thevalve being open and the burner in operation under the boiler just tothe right of the apparatus shown in Fig. 1 and i'nto which thethermostat extends, the water in said boiler becomes heated, causing thesleeve 36 i to expand. As the rod 34 contained in the said sleeve is tosome extent protected from the heat of the water, and also because itscoefiicient of expansion is substantially less than that of the sleeve36, the rod is permitted to pass to the right, the spring 42acting-uponthe lever 25, and swingingthe upperend of same over to theright. -In the position of the parts shown in Figs..1 and 3, theU-spring 26, acting between the upper end of the lever 25 and the lowerend the lever 27, tends to keep the lever 27 in the position shown, sothat the valve 20 is held up,that is, open. When, however,

I f the right-handed swing of the lever 25 passes beyond a,certaincritical point, the action of the U-spring is reversed. that is to say,it

impels the lower end of the lever 27 to the left and consequently itsupper end tothe right, thus bringing a slanting portion or cut offcorner of the upper end of the said lever into contact with the plug 2,3and permitting the valve 20 to fall, thus bringing the parts into theposition shown in Fig. 4. The iiow of gas being thus cutoff, and theframe in the main burner extinguished, the temperais the employment ofa,y quick-acting vvalve control device, which in the here described andillustrated embodiment of the -invention trol same, and which provides alpositive and quick snap action of the valve. When employing thecombination of parts comprising my invention, it is not possiblefor thevalve to remain poised in a partly open and partly closed position, butit must be either open or tightly closed, in other words, there is acritical position of the parts which if varied even very slightly in onedirection causes the Valve to close or if in the other direction causesthe valve to open. 'I am aware that in devices previously known in theart, mechanism adapted to open and close valves automatically bythermostatic action are'well known, and I am also awareA that certainofV such devices employ elements similar to some of Vthe elements whichare comprised in my invention, but so fa'r as I am aware no apparatushas been known in the art which operates as does my inventionl and whichprovides the positive snap action for opening and closing the gas valve,which I have invented.

I do not therefore claim broadly the control of the gas valve bythermostatic means,

Ebut what I. claim as new and desire to securezby Letters Patent is asfollows:

water heaters and the like, comprising in i' is represented by the lever27, in combination 'with the other operating parts which conlllcombination the following elements: a suitable supporting frame orcasing; a gas-control valve; aheat-expansible member adaptedto be placedin proximity to the water to be heated; a swinging lever adapted to beswung by the expansion of said heat-expansible member; a* secondswinging lever one end of which is adjacent said gas valve and the otherend of which is in substantial proximity to the outer end of saidrstnamed lever, said second-named lever being adapted when in voneposition to close said valve and when in another-position to o enr same;and a thrust snap-spring located e- I y mediate position.y

tween the proximate ends of said swinging levers and having its endsoperatively connected to the same respectively and being adapted, whensaid rst-named swingi lever is swung, to swing sai-d second-nam swinginglever and to hold the same either in the position whereby said gas valveis opened or in the position whereby said gas valve is closed but toprevent said second swinging lever from remaining in an inter- 2. Athermostatic gas-control device for water heaters and the like,comprisingI in combination the following elements: a suitable supportingframe or casing; a gas-control valve; a heat-expansible member adaptedto be. placed in proximity to the water to be heateda swinging leveradapted to be swung by t e expansion of said heat-ex-v pansible member;a second swinging lever one end of which-is adjacent said gas valve andthe other end of which is in substantial proximity to the outer end ofsaid firstnamed lever, said second-named lever being adapted when in oneposition to close said valve and when in another position to open same;a thrust snap-s ring located between the proximate ends o said swinginglevers and having its ends operatively connected to the samerespectively and being adapted,

when said first-named swinging vlever is4 swung, to swing saidsecond-named swinging'lever and to hold the same either in the position'wherebyy said gas valve is opened or in the positiony whereby said gasvalve is vclosed but to prevent said second swinging lever fromremaining in an intermediate position; and a spring interposed betweensame; a thrust snap-spring located between the said first-named swinginglever and said casing, adapted to keep said first-named swinglng leverin contact with said heat-expansible member. *l

3. A thermostatic gas-control device for water heaters and the like,comprising in combination the following elements: a suitable supportingframe or casing; a gas-control valve; a heat-expansible member adaptedto be placed in proximity to th'e water to be heated; a swinging leveradapted to be swung by the expansion of said heat-expansible member; asecond swinging lever one end of which is adjacent said gas valve andthe other end of which is in substantial proxlmity to the outer end ofsaid firstnamed lever, said second-named lever bein adapted when in oneposition to close, sai valve and when in another position to open theproximate ends of said swinging levers.

and having its ends operatively connected to the same respectlvely andbeing adapted,

. when said first-named swinging lever is swung, to swing saidsecond-named swinging leverand to hold the same either in the positionwhereby said as valve -is opened or in the position where y said gasvalve is closed but to prevent said second swinging lever from remainingin an intermediate position; a spring interposed between the saidfirst-named swinging lever and said casing adapted to keep saidirst-named swinging lever in contact with said heat-expansib e Amember;and an adjustable stop adapted to` land the other end of which is insubstantial proximity to the outer e'nd of said.A firstnamed lever, saidsecond-named lever bein adapted when in one position to close sai valveand when in another position to open same; a thrust snap-sprin locatedbetween the proximate vends of sai swinging levers and having its endsoperatively connected to the same respectivel and Abeing adapted, whensaid first-name swinging lever is swung, to swing saidsecond-named'swinging lever and to hold the same either 1n the positionwhereby said gas valve is opened or in the position whereby said gasvalve is closed but to prevent said second swinging lever from remainingin an intermediate position; a spring interposed between the saidfirst-named swinging lever and said casing, adapted to keep saidfirst-named swin ing lever in Contact with said heat-,expansib e member;an adjustable stop adapted to operate against the lower por ion of saidfirstnamed swinging lever and hold the same in position, and anadjustable stop adapted to limit the extent of the swing of saldfirstnamed swinging. lever.

In witness whereof I have hereunto signed my name this 21st day ofOctober, 1926.

JOHN G. WRAGG.

